jsglobalobject.h

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        Structure* callbackObjectStructure() const { return d()->callbackObjectStructure.get(); }
        Structure* dateStructure() const { return d()->dateStructure.get(); }
        Structure* emptyObjectStructure() const { return d()->emptyObjectStructure.get(); }
        Structure* errorStructure() const { return d()->errorStructure.get(); }
        Structure* functionStructure() const { return d()->functionStructure.get(); }
        Structure* numberObjectStructure() const { return d()->numberObjectStructure.get(); }
        Structure* prototypeFunctionStructure() const { return d()->prototypeFunctionStructure.get(); }
        Structure* regExpMatchesArrayStructure() const { return d()->regExpMatchesArrayStructure.get(); }
        Structure* regExpStructure() const { return d()->regExpStructure.get(); }
        Structure* stringObjectStructure() const { return d()->stringObjectStructure.get(); }

        void setProfileGroup(unsigned value) { d()->profileGroup = value; }
        unsigned profileGroup() const { return d()->profileGroup; }

        Debugger* debugger() const { return d()->debugger; }
        void setDebugger(Debugger* debugger) { d()->debugger = debugger; }
        
        virtual bool supportsProfiling() const { return false; }
        
        int recursion() { return d()->recursion; }
        void incRecursion() { ++d()->recursion; }
        void decRecursion() { --d()->recursion; }
        
        ScopeChain& globalScopeChain() { return d()->globalScopeChain; }

        virtual bool isGlobalObject() const { return true; }

        virtual ExecState* globalExec();

        virtual bool shouldInterruptScript() const { return true; }

        virtual bool allowsAccessFrom(const JSGlobalObject*) const { return true; }

        virtual bool isDynamicScope() const;

        HashSet<ProgramCodeBlock*>& codeBlocks() { return d()->codeBlocks; }

        void copyGlobalsFrom(RegisterFile&);
        void copyGlobalsTo(RegisterFile&);
        
        void resetPrototype(JSValuePtr prototype);

        JSGlobalData* globalData() { return d()->globalData.get(); }
        JSGlobalObjectData* d() const { return static_cast<JSGlobalObjectData*>(JSVariableObject::d); }

        static PassRefPtr<Structure> createStructure(JSValuePtr prototype)
        {
            return Structure::create(prototype, TypeInfo(ObjectType));
        }

    protected:
        struct GlobalPropertyInfo {
            GlobalPropertyInfo(const Identifier& i, JSValuePtr v, unsigned a)
                : identifier(i)
                , value(v)
                , attributes(a)
            {
            }

            const Identifier identifier;
            JSValuePtr value;
            unsigned attributes;
        };
        void addStaticGlobals(GlobalPropertyInfo*, int count);

    private:
        // FIXME: Fold reset into init.
        void init(JSObject* thisValue);
        void reset(JSValuePtr prototype);

        void setRegisters(Register* registers, Register* registerArray, size_t count);

        void* operator new(size_t); // can only be allocated with JSGlobalData
    };

    JSGlobalObject* asGlobalObject(JSValuePtr);

    inline JSGlobalObject* asGlobalObject(JSValuePtr value)
    {
        ASSERT(asObject(value)->isGlobalObject());
        return static_cast<JSGlobalObject*>(asObject(value));
    }

    inline void JSGlobalObject::setRegisters(Register* registers, Register* registerArray, size_t count)
    {
        JSVariableObject::setRegisters(registers, registerArray);
        d()->registerArraySize = count;
    }

    inline void JSGlobalObject::addStaticGlobals(GlobalPropertyInfo* globals, int count)
    {
        size_t oldSize = d()->registerArraySize;
        size_t newSize = oldSize + count;
        Register* registerArray = new Register[newSize];
        if (d()->registerArray)
            memcpy(registerArray + count, d()->registerArray.get(), oldSize * sizeof(Register));
        setRegisters(registerArray + newSize, registerArray, newSize);

        for (int i = 0, index = -static_cast<int>(oldSize) - 1; i < count; ++i, --index) {
            GlobalPropertyInfo& global = globals[i];
            ASSERT(global.attributes & DontDelete);
            SymbolTableEntry newEntry(index, global.attributes);
            symbolTable().add(global.identifier.ustring().rep(), newEntry);
            registerAt(index) = global.value;
        }
    }

    inline bool JSGlobalObject::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
    {
        if (JSVariableObject::getOwnPropertySlot(exec, propertyName, slot))
            return true;
        return symbolTableGet(propertyName, slot);
    }

    inline bool JSGlobalObject::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot, bool& slotIsWriteable)
    {
        if (JSVariableObject::getOwnPropertySlotForWrite(exec, propertyName, slot, slotIsWriteable))
            return true;
        return symbolTableGet(propertyName, slot, slotIsWriteable);
    }

    inline JSGlobalObject* ScopeChainNode::globalObject() const
    {
        const ScopeChainNode* n = this;
        while (n->next)
            n = n->next;
        return asGlobalObject(n->object);
    }

    inline JSValuePtr Structure::prototypeForLookup(ExecState* exec) const
    {
        if (typeInfo().type() == ObjectType)
            return m_prototype;

        if (typeInfo().type() == StringType)
            return exec->lexicalGlobalObject()->stringPrototype();

        ASSERT(typeInfo().type() == NumberType);
        return exec->lexicalGlobalObject()->numberPrototype();
    }

    inline StructureChain* Structure::prototypeChain(ExecState* exec) const
    {
        // We cache our prototype chain so our clients can share it.
        if (!isValid(exec, m_cachedPrototypeChain.get())) {
            JSValuePtr prototype = prototypeForLookup(exec);
            m_cachedPrototypeChain = StructureChain::create(prototype.isNull() ? 0 : asObject(prototype)->structure());
        }
        return m_cachedPrototypeChain.get();
    }

    inline bool Structure::isValid(ExecState* exec, StructureChain* cachedPrototypeChain) const
    {
        if (!cachedPrototypeChain)
            return false;

        JSValuePtr prototype = prototypeForLookup(exec);
        RefPtr<Structure>* cachedStructure = cachedPrototypeChain->head();
        while(*cachedStructure && !prototype.isNull()) {
            if (asObject(prototype)->structure() != *cachedStructure)
                return false;
            ++cachedStructure;
            prototype = asObject(prototype)->prototype();
        }
        return prototype.isNull() && !*cachedStructure;
    }

    inline JSGlobalObject* ExecState::dynamicGlobalObject()
    {
        if (this == lexicalGlobalObject()->globalExec())
            return lexicalGlobalObject();

        // For any ExecState that's not a globalExec, the 
        // dynamic global object must be set since code is running
        ASSERT(globalData().dynamicGlobalObject);
        return globalData().dynamicGlobalObject;
    }

    class DynamicGlobalObjectScope : Noncopyable {
    public:
        DynamicGlobalObjectScope(CallFrame* callFrame, JSGlobalObject* dynamicGlobalObject) 
            : m_dynamicGlobalObjectSlot(callFrame->globalData().dynamicGlobalObject)
            , m_savedDynamicGlobalObject(m_dynamicGlobalObjectSlot)
        {
            m_dynamicGlobalObjectSlot = dynamicGlobalObject;
        }

        ~DynamicGlobalObjectScope()
        {
            m_dynamicGlobalObjectSlot = m_savedDynamicGlobalObject;
        }

    private:
        JSGlobalObject*& m_dynamicGlobalObjectSlot;
        JSGlobalObject* m_savedDynamicGlobalObject;
    };

} // namespace JSC

#endif // JSGlobalObject_h